[INFO] fetching crate simple-storage 0.0.2...
[INFO] checking simple-storage-0.0.2 against try#39e1293fce4b650061e85dda88aa428f726a8444 for pr-88041
[INFO] extracting crate simple-storage 0.0.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate simple-storage 0.0.2 on toolchain 39e1293fce4b650061e85dda88aa428f726a8444
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate simple-storage 0.0.2
[INFO] finished tweaking crates.io crate simple-storage 0.0.2
[INFO] tweaked toml for crates.io crate simple-storage 0.0.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 94b628d7cbe5c07492357ce07aa71180e8d46fc8bd38d1e0f6cf0a85c753827b
[INFO] running `Command { std: "docker" "start" "-a" "94b628d7cbe5c07492357ce07aa71180e8d46fc8bd38d1e0f6cf0a85c753827b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "94b628d7cbe5c07492357ce07aa71180e8d46fc8bd38d1e0f6cf0a85c753827b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "94b628d7cbe5c07492357ce07aa71180e8d46fc8bd38d1e0f6cf0a85c753827b", kill_on_drop: false }`
[INFO] [stdout] 94b628d7cbe5c07492357ce07aa71180e8d46fc8bd38d1e0f6cf0a85c753827b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+39e1293fce4b650061e85dda88aa428f726a8444" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4a2c130e635bff1e7788d5ad735a74bfea0c8ab22c9da4db1e040ae50c1f708a
[INFO] running `Command { std: "docker" "start" "-a" "4a2c130e635bff1e7788d5ad735a74bfea0c8ab22c9da4db1e040ae50c1f708a", kill_on_drop: false }`
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling serde_derive v1.0.127
[INFO] [stderr]     Checking serde v1.0.127
[INFO] [stderr]     Checking serde_json v1.0.66
[INFO] [stderr]     Checking simple-storage v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/lib.rs:91:5
[INFO] [stdout]    |
[INFO] [stdout] 91 |     &self.content.insert(key, value);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 91 |     let _ = &self.content.insert(key, value);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/lib.rs:91:5
[INFO] [stdout]    |
[INFO] [stdout] 91 |     &self.content.insert(key, value);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 91 |     let _ = &self.content.insert(key, value);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 13.11s
[INFO] running `Command { std: "docker" "inspect" "4a2c130e635bff1e7788d5ad735a74bfea0c8ab22c9da4db1e040ae50c1f708a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4a2c130e635bff1e7788d5ad735a74bfea0c8ab22c9da4db1e040ae50c1f708a", kill_on_drop: false }`
[INFO] [stdout] 4a2c130e635bff1e7788d5ad735a74bfea0c8ab22c9da4db1e040ae50c1f708a